Engineering Three-Dimensional Bendable Helix Conduits for Peripheral Nerve Regeneration via Hybrid Electrotechnologies

Nerve guidance conduits (NGCs) are considered as the best alternative approach to autologous nerve grafting for treating peripheral nerve injuries (PNI). The bendable NGCs are desirable in practical use but are still difficult to fabricate. In this study, the hybrid electrotechnologies combining electrohydrodynamic (EHD) printing and electrospinning were applied to produce a novel bendable helix conduit with tunable flexibility. Helical polycaprolactone (PCL) foundations were constructed via EHD printing for mechanical support, on which electrospinning PCL membrane was coated to form the bendable helix conduits and keep the entire structure stable. The effects of helical foundation with different helical height on the properties of NGCs were analyzed. In addition, these three-dimensional (3D) bendable helix conduits had excellent resistance to compression and fatigue. Moreover, the bendable conduits had higher specific surface area, which is beneficial to the adsorption of RSC96 cells. Therefore, the 3D bendable helix conduits show great potential in clinical application for treating PNI.